Liblouis User's and Programmer's Manual

2.6.4 Computer braille ¶

For computer braille there are only two braille indicators, for the beginning and end of a sequence of characters to be rendered in computer braille. Such a sequence may also have other emphasis. The computer braille indicators are applied not only when computer braille is indicated in the typeform parameter, but also when a sequence of characters is determined to be computer braille because it contains a subsequence defined by the compbrl opcode (see compbrl).

begcomp dots

This braille indicator is placed before a sequence of characters translated in computer braille, whether this sequence is indicated in the typeform parameter (see typeform parameter) or inferred because it contains a subsequence specified by the compbrl opcode (see compbrl).

endcomp dots

This braille indicator is placed after a sequence of characters translated in computer braille, whether this sequence is indicated in the typeform parameter (see typeform parameter) or inferred because it contains a subsequence specified by the compbrl opcode (see compbrl).